Heteroaryl carboxylic acids are useful as starting materials and reagents in the preparation of a wide variety of industrially useful compounds. For example, U.S. Pub. No. 2014/0039197 A1 reports that heteroaryl acyl chlorides prepared from heteroaryl carboxylic acids can be reacted with N-hydroxyamidines in the preparation of 3,5-disubstituted-1,2,4-oxadiazoles, which are useful for, in part, nematode control in agriculture. For example, heteroaryl carboxylic acids can be used to prepare 2-thiophenecarbonyl chloride, which is useful in the preparation of tioxazafen (3-phenyl-5-(2-thienyl)-1,2,4-oxadiazole) by reaction with benzamide oxime. While methods for preparing heteroaryl carboxylic acids are known in the art, alternative routes that may result in a more efficient synthesis are highly desirable.
Citation of any reference herein is not to be construed as an admission that such reference is prior art to the present application.